Prolific Sea-Observing Satellite Turns 10

An
international oceanography satellite that is tracking the ongoing rise in
global sea level marks its 10th year in orbit today.

Designed
for a three-to-five-year mission, the joint U.S./European Ocean Surface
Topography Mission (OSTM) on the Jason-2 satellite has now made more than
47,000 trips around our home planet, measuring sea level change across the globe,
observing ocean currents, studying climate phenomena such as El Nino and La
Nina, and monitoring the long-term rise in global mean sea level. In January
2016, it was joined in orbit by its follow-on mission, Jason-3. NASA's Jet
Propulsion Laboratory in Pasadena, California, manages NASA's portion of both
missions.

In
July 2017, Jason-2 began a new science mission when it was maneuvered into a
slightly lower orbit. In this new orbit, Jason-2 is collecting data along a
series of very closely spaced ground tracks, just 5 miles (8 kilometers) apart.
It will take just over a year for Jason-2 to complete one cycle of these new
ground tracks, which provide a very accurate and high-resolution estimate of
the mean sea surface. The pull of gravity from underwater mountains and other
features of the sea floor helps to shape the mean sea surface. These new
surface measurements are already being used by scientists to improve maps of
the shape and depth of the sea floor, resolving many previously unknown
seamounts and other geologic features on the ocean bottom. The new maps will
also allow for advances in ocean modeling, naval operations and solid Earth
dynamics.

Jason-2
data from the new orbit are used by operational agencies to provide societal
and strategic benefits, such as real-time information used for deriving ocean
currents; improving marine, fishery and naval operations; and calculating
tropical cyclone heat potential to improve forecasts of the intensity of
tropical hurricanes and cyclones.

"Along
with Jason-3, Jason-2 has extended the record of global sea level rise into a
third decade," said Glenn Shirtliffe, Jason-2 project manager at JPL.

NASA
is currently working with its partners -- the European Space Agency, the
National Oceanic and Atmospheric Administration, the Centre National d'etudes
Spatiales and the European
Organisation for the Exploitation of Meteorological Satellites -- on future generations of satellite altimeters. The
instruments are projected for launch in the next decade. They include the
Sentinel-6/Jason Continuity of Service (Jason-CS) and Surface Water and Ocean
Topography (SWOT) missions.

"In addition to measuring ocean
circulation and revealing the ocean's role in Earth's climate, Jason-2 and
Jason-3 measure the rise in global sea level caused
by global warming," said Josh Willis, JPL oceanographer and NASA's project
scientist for both missions. "Melting ice and expanding seawater drive
global sea levels higher and higher each year. The rise has become a powerful
reminder of how fast humans are changing the climate. These missions keep our
finger on the pulse of climate change."

Other
significant science results from the Jason-2 mission include studies of ocean
circulation; the ties between the ocean and the atmosphere; and improved global
climate forecasts and predictions.

"The
10th anniversary of the launch of Jason-2 is also a landmark in the development
of operational oceanography, as this was the first Jason mission involving two
operational agencies, EUMETSAT and NOAA," said EUMETSAT Director-General Alain
Ratier. "This paved the way for the transition from highly successful research
missions to an operational altimeter system, which has now turned to reality
with Jason-3, Jason-CS/Sentinel-6 and Sentinel-3 providing data until
2030."

"After 10 years of excellent service, we're excited
that Jason-2 is continuing to help forecast hurricane intensity and
monitor winds and waves, while taking on a new mission of mapping
unexplored parts of the ocean," said Eric Leuliette, NOAA's Jason program
and project scientist.

For
more information on Jason-2 and other satellite altimetry missions, visit: